view tests/test-doctest.py @ 49000:dd6b67d5c256 stable

rust: fix unsound `OwningDirstateMap`

As per the previous patch, `OwningDirstateMap` is unsound. Self-referential
structs are difficult to implement correctly in Rust since the compiler is
free to move structs around as much as it wants to. They are also very rarely
needed in practice, so the state-of-the-art on how they should be done within
the Rust rules is still a bit new.

The crate `ouroboros` is an attempt at providing a safe way (in the Rust sense)
of declaring self-referential structs. It is getting a lot attention and was
improved very quickly when soundness issues were found in the past: rather than
relying on our own (limited) review circle, we might as well use the de-facto
common crate to fix this problem. This will give us a much better chance of
finding issues should any new ones be discovered as well as the benefit of
fewer `unsafe` APIs of our own.

I was starting to think about how I would present a safe API to the old struct
but soon realized that the callback-based approach was already done in
`ouroboros`, along with a lot more care towards refusing incorrect structs.

In short: we don't return a mutable reference to the `DirstateMap` anymore, we
expect users of its API to pass a `FnOnce` that takes the map as an argument.
This allows our `OwningDirstateMap` to control the input and output lifetimes
of the code that modifies it to prevent such issues.

Changing to `ouroboros` meant changing every API with it, but it is relatively
low churn in the end. It correctly identified the example buggy modification of
`copy_map_insert` outlined in the previous patch as violating the borrow rules.

Differential Revision: https://phab.mercurial-scm.org/D12429

# this is hack to make sure no escape characters are inserted into the output

from __future__ import absolute_import
from __future__ import print_function

import doctest
import os
import re
import subprocess
import sys

ispy3 = sys.version_info[0] >= 3

if 'TERM' in os.environ:
    del os.environ['TERM']


class py3docchecker(doctest.OutputChecker):
    def check_output(self, want, got, optionflags):
        want2 = re.sub(r'''\bu(['"])(.*?)\1''', r'\1\2\1', want)  # py2: u''
        got2 = re.sub(r'''\bb(['"])(.*?)\1''', r'\1\2\1', got)  # py3: b''
        # py3: <exc.name>: b'<msg>' -> <name>: <msg>
        #      <exc.name>: <others> -> <name>: <others>
        got2 = re.sub(
            r'''^mercurial\.\w+\.(\w+): (['"])(.*?)\2''',
            r'\1: \3',
            got2,
            re.MULTILINE,
        )
        got2 = re.sub(r'^mercurial\.\w+\.(\w+): ', r'\1: ', got2, re.MULTILINE)
        return any(
            doctest.OutputChecker.check_output(self, w, g, optionflags)
            for w, g in [(want, got), (want2, got2)]
        )


def testmod(name, optionflags=0, testtarget=None):
    __import__(name)
    mod = sys.modules[name]
    if testtarget is not None:
        mod = getattr(mod, testtarget)

    # minimal copy of doctest.testmod()
    finder = doctest.DocTestFinder()
    checker = None
    if ispy3:
        checker = py3docchecker()
    runner = doctest.DocTestRunner(checker=checker, optionflags=optionflags)
    for test in finder.find(mod, name):
        runner.run(test)
    runner.summarize()


DONT_RUN = []

# Exceptions to the defaults for a given detected module. The value for each
# module name is a list of dicts that specify the kwargs to pass to testmod.
# testmod is called once per item in the list, so an empty list will cause the
# module to not be tested.
testmod_arg_overrides = {
    'i18n.check-translation': DONT_RUN,  # may require extra installation
    'mercurial.dagparser': [{'optionflags': doctest.NORMALIZE_WHITESPACE}],
    'mercurial.keepalive': DONT_RUN,  # >>> is an example, not a doctest
    'mercurial.posix': DONT_RUN,  # run by mercurial.platform
    'mercurial.statprof': DONT_RUN,  # >>> is an example, not a doctest
    'mercurial.util': [{}, {'testtarget': 'platform'}],  # run twice!
    'mercurial.windows': DONT_RUN,  # run by mercurial.platform
    'tests.test-url': [{'optionflags': doctest.NORMALIZE_WHITESPACE}],
}

fileset = 'set:(**.py)'

cwd = os.path.dirname(os.environ["TESTDIR"])

if not os.path.isdir(os.path.join(cwd, ".hg")):
    sys.exit(0)

files = subprocess.check_output(
    "hg files --print0 \"%s\"" % fileset,
    shell=True,
    cwd=cwd,
).split(b'\0')

if sys.version_info[0] >= 3:
    cwd = os.fsencode(cwd)

mods_tested = set()
for f in files:
    if not f:
        continue

    with open(os.path.join(cwd, f), "rb") as fh:
        if not re.search(br'\n\s*>>>', fh.read()):
            continue

    if ispy3:
        f = f.decode()

    modname = f.replace('.py', '').replace('\\', '.').replace('/', '.')

    # Third-party modules aren't our responsibility to test, and the modules in
    # contrib generally do not have doctests in a good state, plus they're hard
    # to import if this test is running with py2, so we just skip both for now.
    if modname.startswith('mercurial.thirdparty.') or modname.startswith(
        'contrib.'
    ):
        continue

    for kwargs in testmod_arg_overrides.get(modname, [{}]):
        mods_tested.add((modname, '%r' % (kwargs,)))
        if modname.startswith('tests.'):
            # On py2, we can't import from tests.foo, but it works on both py2
            # and py3 with the way that PYTHONPATH is setup to import without
            # the 'tests.' prefix, so we do that.
            modname = modname[len('tests.') :]

        testmod(modname, **kwargs)

# Meta-test: let's make sure that we actually ran what we expected to, above.
# Each item in the set is a 2-tuple of module name and stringified kwargs passed
# to testmod.
expected_mods_tested = set(
    [
        ('hgext.convert.convcmd', '{}'),
        ('hgext.convert.cvsps', '{}'),
        ('hgext.convert.filemap', '{}'),
        ('hgext.convert.p4', '{}'),
        ('hgext.convert.subversion', '{}'),
        ('hgext.fix', '{}'),
        ('hgext.mq', '{}'),
        ('mercurial.changelog', '{}'),
        ('mercurial.cmdutil', '{}'),
        ('mercurial.color', '{}'),
        ('mercurial.dagparser', "{'optionflags': 4}"),
        ('mercurial.dirstateutils.v2', '{}'),
        ('mercurial.encoding', '{}'),
        ('mercurial.fancyopts', '{}'),
        ('mercurial.formatter', '{}'),
        ('mercurial.hg', '{}'),
        ('mercurial.hgweb.hgwebdir_mod', '{}'),
        ('mercurial.match', '{}'),
        ('mercurial.mdiff', '{}'),
        ('mercurial.minirst', '{}'),
        ('mercurial.parser', '{}'),
        ('mercurial.patch', '{}'),
        ('mercurial.pathutil', '{}'),
        ('mercurial.pycompat', '{}'),
        ('mercurial.revlogutils.deltas', '{}'),
        ('mercurial.revset', '{}'),
        ('mercurial.revsetlang', '{}'),
        ('mercurial.simplemerge', '{}'),
        ('mercurial.smartset', '{}'),
        ('mercurial.store', '{}'),
        ('mercurial.subrepo', '{}'),
        ('mercurial.templater', '{}'),
        ('mercurial.ui', '{}'),
        ('mercurial.util', "{'testtarget': 'platform'}"),
        ('mercurial.util', '{}'),
        ('mercurial.utils.dateutil', '{}'),
        ('mercurial.utils.stringutil', '{}'),
        ('mercurial.utils.urlutil', '{}'),
        ('tests.drawdag', '{}'),
        ('tests.test-run-tests', '{}'),
        ('tests.test-url', "{'optionflags': 4}"),
    ]
)

unexpectedly_run = mods_tested.difference(expected_mods_tested)
not_run = expected_mods_tested.difference(mods_tested)

if unexpectedly_run:
    print('Unexpectedly ran (probably need to add to list):')
    for r in sorted(unexpectedly_run):
        print('  %r' % (r,))
if not_run:
    print('Expected to run, but was not run (doctest removed?):')
    for r in sorted(not_run):
        print('  %r' % (r,))